Railway signaling system



1,572,570 L. E. SPRAY RAILWAY SIGNALING SYSTEM Filed may 4, 1925 2 Sheets-Sheet 1 Feb. 9 1926.

INVENILOR'.

BY 63 M ATTORNEY J V RS m u m u n 1,572,570 L. E. SPRAY RAILWAY SIGNALING SYSTEM v Filed May 4, 1925 Sheets-She et 2 v ,Y m \h w 12 m MW QM NMV M \KE w Kw m a m f SEQ ENM WQ mfi wk WM. w fl ANQ\ Um D 35 a. Q m \QN QNN UNN ,\\M.N1 w o m. n N Us K m ll! m wm FIiP H W r. b

Patented Feb. 9, 1926.

UITEEF STATES:

PATENT OFFICE.

LESTER E. SPRAY, 0]? WILKINSBURG, PENESYLVANIA, .AESIGNOR TO THE UNION SW'ITCH 62; SIGNAL COMPANY, 01*" S'WISEJVALE, PENNSYLVANIA, A CORPORATION OF PENNSYLVANIA.

RAILWAY SIGNALING SYSTEM.

Application filed May 4-, 1925. Serial No. 27,740.

To uZZ arc/20m 2'25 may concern Be it known that I, LESTER SPRAY, a citizen of the United States, residing at Wit hinsburg, in the county of Alle heny and State of Pennsylvania, have invented certain new and useful Improvements in Railway Signaling Systems, of which the fol lowing is a specification.

My invention relates to railway signaling systems, and particularly to systems of the type wherein a stop indication and two cantion indications are given in the r ar of a train.

I will describe one form of system enibodying my invention, and will then point out the novel features thereof in claims.

The accompanying drawings, when placed end to end, are a diagrammatic view showing one form of signaling system embod ing my invention.

Referring to the drawings, the reference characters 1 and 1 designate the track rails of a railway along which tratlic normally moves in the direction indicated by the arrows. These rails are divided by insulated joints 35 to form a plurality of track sections of which three complete sections AB, BC and (1-D, are shown in the drawings.

Located adjacent the entrance end of each section is a signal which is designated by the reference character S, with an exponent corresponding to the location. Each of these signals in the form here shown is of the one-arm three-position semaphore type, arranged to indicate proceed, caution and stop, according is the arm is in the vertical, the inclined, or the horizontal position.

Each track section is provided with a track circuit comprising a source of current connected across the rails at the exit end of the section, and a track relay connected across the rails at the entrance end of th section. As here shown, the source of cur rent for each track circuit is a transformer designated by the reference character J, with an exponent corresponding to the loca tion The secondary 7 of each transformer is connected across the track rails through a reactance 8 in the manner hereinafter explained. The primary 6 of each track transformer J is connected with the secondary 5 of a line transformer designated by the referencecharacte-r H, with an exponent corresponding to the location. The primary 4 of each transformer H is connected with a transmission line G which is constantly supplied with alternating signaling current by a generator F. The track relay for each section is designated by the reference character T, with an exponent corresponding to the location, and comprises a track winding 2 constantly connected across the rails of the section, and a local winding 3 constantly supplied with alternating current from the secondary 5 of the adjacent line transformer H. Each track relay T is responsive, therefore, to reversals of the relative polarity of the current in the track circuit of the associated section.

Each alternate section, such as section A-B and section CD, is provided with an auxiliary relay designated by the reference character E, with an exponent corresponding to the location, and each of these auxiliary relays E is controlled by the signal for the second section in advance. Referring specifically to relay E the circuit for this relay passes from the secondary 5 of line transformer H through wire 18, circuit controller l9 operated by signal S wire 20, winding of relay E and wire 21 to the secondary 5 of transformer H Circuit controller 19 is closed when. signal S in dicates proceed or caution, but is open when this signal indicates stop, and, consequently, relay E is energized only when signal S indicates proceed or caution.

Each signal S operates a pole-changer designated by the reference character P, with an exponent corresponding to the location, and each pole-changer is included in the track circuit for the section next in the rear. The selective polarity of the track circuit current for each of the alternate sections AB and C-D is controlled solely by the pole-changer P associated with the track circuit for such section. Referring, for example, to section C-D, when signal S indicates proceed or caution, pole-changer P is in the normal position wherein current of normal relative polarity is supplied to the rails of section C-D, with the result that the track relay T is energized in normal direction wherein the contacts of this relay are swung to their left-hand positions. When signal S indicates stop, however, pole-changer P is in the reverse position, so that track relay T is energized in the reverse direction wherein the contacts of this relay are swung to their right-hand positions.

The relative polarity of the track circuit current in each intermediate section is determined by the associated pole-changer P and also by the contacts 25 and 32 of the track relay for the section next in advance. Referring specifically to section BC, when signal S indicates proceed and track relay T is energized in the normal direction, that is, when these parts are in the positions shown in the drawing, track circuit current for section B G flows from the secondary 7 of track transformer J through reactance 8, right-hand arm 22 of pole-changer P wire 23 and 2 1, normal contact 2525 of track relay T wires 26 and 27, to track rail 1, and from track rail 1, through Wires 28 and 29, left-hand arm 30 of pole-changer P wire 34, contact 3232 of relay T and wire 33 to the secondary 7 of transformer J The current which is then supplied to the rails of section BC is of normal relative polarity, so that track relay T is energized in the normal direction and the contacts of this relay are swung to their left-hand positions, as shown in the drawin I will now assume that track relay T is de-energized, and thatsignal S indicates stop, this being the condition as sumed by these parts when section AB is occupied by a train. Pole-changer P will then be reversed and track circuit current for section BC will flow from the secondary 7 of transformer J through reactance 8, right-hand arm 22 of the polechanger P wires 29 and 28 to track rail 1 of section BC, and from track rail 1 of this section, through wires 27 and 36, back contact 32 32 of relay T and wire 33 to secondary 7 of transformer J The track circuit current which is then supplied to section BC is of reverse relative polarity, so that track relay T will be energized in the reverse direction, with the result that contacts of this relay will be swung to their right-hand positions. I will now assume that track relay T is energized in the reverse direction and that signal S indicates caution. Track circuit current for section BC will then flow from the secondary 7 of transformer J through reactance 8, right-hand arm 22 of pole-changer P wires 23 and 24:, reverse contact 25-25 wires 31 and 28, to track rail 1, and from track rail 1, through wires 27 and 36, reverse contact 32 32 of track relay T and wire 33 to secondary 7 of transformer J The track circuit current which is then supplied to section 13-0 is still of reverse relative polarity, so that track relay T is still energized in the reverse direction. I will now assume that track relay T is energized in the normal direction, but that signal S continues to indicate caution. Pole-changer P is then in the normal position, so that current of normal relative polarity is supplied to the rails of section BC through the same path as when signal S is in the. proceed position and relay T is energized in normal direction.

The signal S for each alternate track section, such as 11-13 and CD, is controlled jointly by the associated track relay T and the associated auxiliary relay E. Referring particularly to signal S, this signal is provided with a caution indication circuit which is closed whenever'track relay T is energized in the normal or the reverse direction, this circuit being from secondary 5 of line transformer H through wire 38, normal contact 9-9 or reverse contact 99 of re lay T wire 10, operating mechanism of signal S wire 11, normal contact 1212 or reverse contact 12 12 of relay T and wire 37 to the secondary 5 of transformer H Signal S is provided with a proceed indication circuit which is energized whenever track relay T is energized in the normal direction and the auxiliary relay E is energized; this circuit passes from the secondary 5 of transformer H through wire 38, normal contact 9-4) of track relay T normal contact 1t1l= of the same relay, wire 15, contact 16 of relay E wire 17, operating mechanism of signal S wire 11, normal contact 1212 of relay T and wire 37 to the secondary 5 of transformer H Signal S for the alternate section CD is provided with circuits which are similar to those for signal S The signal for each intern'iediate section is controlled only by the track relay for its section. Referring, for example, to signal S this signal is provided with a cantion indication circuit which is closed when track relay T is energized in reverse direction, this circuit being from secondary 5 of transformer H through wire 38, reverse contact 99 of relay T wire 10, operating mechanism of signal S, wire 11, reverse contact 12"12 of relay T and wire 37 to secondary 5 of transformer H. Signal S is also'provided with a proceed indication circuit which is closed when track relay T is energized in the normal direction, this circuit being from secondary 5 of transformer H through wire 38, normal contact 99 of relay T wire 13, operating 1 mechanism of signal S wire 11, normal contact 12 12 of relay T and wire 37 to the secondary of transformer H The circuits for signal S are similar to the circuits just traced for ignal S The operation of the system is as follows: WV'hen a train moving toward the left, that is, in the direction indicated by the arrow, enters section C-D, it de-energizes track relay T so that signal S moves to the stop polarity is supplied to the position. As the train enters section B C, it tie-energizes track relay T so that signal s moves to the stop position, but as the rear end of the train leaves section CD track relay T becomes energized in the reverse direction because pole-changer P is now in the reverse position due to signal S being in the stop position. The caution indication circuit for signal S is therefore closed at contacts 9 and 12 to relay 'l so that this signal moves to the caution position. As the train enters section AB it tie-energizes track relay T so that signal S moves to the stop positon. As soon as the rear end of he train leaves section B-C, track relay T becomes energized in the reverse direction, because pole-changer P is in the reverse position and track relay T is tie-energized. Signal 8 therefore moves to the caution position, with the re sult that pole-changer P returns to its normal position, and so track circuit current of normal relative polarity is supplied to .section CD. Track relay T therefore becomes energized in the normal. direction, but auxiliary relay E is de-energzed because signal S is in the stop position. It follows that signal S remains in the caution position while the train occupies section lib-15. As the train enters the section to the left of point A, it tie-energizes track relay T so that signal S moves to the stop position. As the rear end of the train leaves section AB, current of reverse relative rails of this sec tion because pole-changer P is reversed, and so track relay T becomes energized in the reverse direction. This causes signal S to move to the caution position, thereby closing circuit controller 1%). Auxiliary relay E then becomes energized, so that signal S moves to the proceed position. Signal S now be ng in the caution position, pole-changer P is in its normal position,

but track relay T is energized in the rev verse direction, so that the current supplied to the rails of section B-C is still of reverse relative polarIty. Track relay T continues to be energized in the reverse direction, so that signal S continues to indicate caution. As the train passes out of the section to the left of point A, signal S will return to the caution position so that polechanger l3 will be restored to its normal position, thereby supplying track circuit current of normal relative polarity to section AB. Track relay T will then become energized in normal direction and signal S being in the caution position polechanger P willjzbe in] its normal position with the result that the track circuit current sup plied to the rails of section BC will be of normal relative polarity. Track relay T will then be energized in the normal direction and signal S will indicate proceed.

Signal S will return to the proceed position when the train passes the third signal in advance of point B, and signal S will likewise return to the proceed position when the train passes the third signal in acvance of point A.

One feature of my invention is the fact that an auxiliary relay E is required at only every other signal location, so that I require only hall as man auxiliary relays as have heretofore bec required for double-caution indication signaling.

Although I have herein shown and described only one form of signal ng system embodying my invention, it is understood that various changes and modifications may be made therein within the scope of the appended claims without departing l lOlll the spirit and scope of my invention.

Having thus described my invention, what I c aim is:

1. In combination, a railway track divided into successive sections, a traci: circuit for each section including a source of current and a track relay responsive to reversals ot' the relative polarity of the track circuit current an auxiliary relay for each alternate section, a signal for each section,

means i'or controlling the signal to: each of said alternate sections by the track relay and the auxiliary relay for the associated section, means for controlling the signal for each intermediate section by the track relay for the associated section, a pole-changer associated with each signal and included in the track circuit for the section next in the rear, contacts of the track relay for each of said alternate sections included in the track circuit for the section in the rear for causing the track circuit current in such section in the rear to be of reverse relative polarity when such track relay is energized in reverse direction and also when it is deenergized, and means for controlling each said auxiliary relay by the signal for the second section in advance.

2. In combination, a railway track divided into successive sections, a track relay for each section responsive to reversals of relative polarity of the track circuit current in the rails of the section, a signal for each section, means controlled by the signal and the track relay of each alternate section for supplying the section next in the rear with track circuit current of normal relative polarity when the signal indicates proceed or caution and the track relay is energized in normal direction and with track circuit current of reverse relative polarity under all other conditions means controlled by the signal for each intermediate section for supplying the section next in the rear with track circuit current of normal relative polarity when the signal indicates proceed or cantion and of reverse relative polarity when the signal indicates stop, an auxiliary re-' lay for each of said alternate sections energized when the signal for the second section in advance indicates proceed or caution but not when it indicates stop, means for causing the signal for each of said alternate sections to indicate proceed when the associated track relay is energized in normal direction and the associated auxiliary relay is energized but to indicate caution when the associated track relay is energized in normal or reverse direction and the associated auxiliary relay is de-energized, and means for causing the signal "for each intermediate section to indicate proceed r caution according as the associated track relay is energized in normal or reverse direction.

3. In combination, a railway track divided into successive sections, a track circuit for each section including a source of current and a track relay responsive to reversals of the relative polarity of the track circuit current, a signal for each section, means for each alternate section for controlling the relative polarity of the track circuit current in the section by only the signal for the section in advance, means for each intermediate section for controlling the relative polarity of the track circuit current in the section by the signal and also the track relay for the section next in advance, an auxiliary relay for each of said alternate sections controlled by the signal for the second section in advance, means for controlling the signal for each of said alternate sections by the associated track relay and auxiliary relay, and means for controlling the signal for each intermediate section by the associated track relay.

4. In combination, a railway track divided into sections a track relay for each section responsive to reversals of the relative polarity of the track circuit current in the rails of the section, a signal for each section, means controlled jointly by the signal and the track relay of each alternate section for supplying track circuit current of normal or reverse relative polarity to the section next in the rear, means controlled by the signal only of each intermediate section for supplying track circuit current of normal or reverse relative polarity to the section next in the rear, means for controlling the signal for each or said alternate sections by the associated track relay and by the signal for the second section in advance, and means for controlling the signal for each of said intermediate sections by only the associated track relay.

in testimony whereof I afiix my signature.

- LESTER E. SPRAY, 

